Going to college is a great experience: new friends, new classes and if you’re really lucky, a stylish roommate with the same shoe size. Doubling your closet content can be a serious plus, assuming you follow some basic rules.

Don’t: Take without asking. This is the key to any successful sharing agreement. Even just sending a quick text to ask for permission can save you from future arguments.

Do: Understand differences in body types. Even though you both may be able to fit into a size medium top, don’t try to squeeze your size 8 hips into a size 2 pair of jeans. You’ll feel more embarrassed when something doesn’t fit than if you’re honest with yourself about your body beforehand.

Don’t: Lend out your favorite clothing. Garments you have a serious attachment to should stay in your closet to be worn by you and you only. Accidents happen and you don’t want to end a friendship over some spilled beer.

Do: Play fair. If you’re always borrowing her shoes and skirts, she has free reign of your tops and jewelry. No one wants to feel like they’re being taken advantage of.

Don’t: Lie about damage to her clothing. Stains and tears happen, so the sooner you own up to the damage, the sooner you can do something about it. Just know that if it needs to be taken to a tailor or dry-cleaner for a quick fix, it’s your job to pick up the tab.

Do: Agree on a wash-and-return policy. If you know your shirt needs to lay flat to dry or you prefer to have something dry-cleaned, let your roommate know. This way you’ll avoid any shrunken shirts or damaged fabric. Some roommates will prefer that you return something right after you wear it without washing it to avoid misplaced clothing or damage.

Don’t: Hoard outfits. Try to return clothing as quickly as possible. It keeps things from getting lost and will help you avoid unnecessary arguments if your roomie decides she wants to take a closet inventory.

Do: Offer your style expertise. If you see your roommate struggling to put together the perfect party ensemble, suggest a dress from your wardrobe to help her out. It’s safe to say she’ll do the same for you in the future.

Don’t: Borrow something you can’t replace. If you know your roommate has an adorable top from her study abroad trip to Spain, avoid wearing it. If something happens to it, there’s no way for you to replace it.

Finally, the most important rule to remember is your roommate’s closet is not actually your closet. If you both want to wear the same nude pumps tonight, the owner has dibs. After all, she’s the reason you have any access to them in the first place.